Hi Helen

A simple way to do this would be to backup a course with blocks in the order you like and restore the course to a new course.

If there are too many courses for this then editing the config.php file in Totara as below.

The file config-dist.php has details on what needs to be added to the file 

// These variables define DEFAULT block variables for new courses

// If this one is set it overrides all others and is the only one used.

//      $CFG->defaultblocks_override = 'participants,activity_modules,search_forums,course_list:news_items,calendar_upcoming,recent_activity';

//

// These variables define the specific settings for defined course formats.

// They override any settings defined in the formats own config file.

//      $CFG->defaultblocks_site = 'site_main_menu,course_list:course_summary,calendar_month';

//      $CFG->defaultblocks_social = 'participants,search_forums,calendar_month,calendar_upcoming,social_activities,recent_activity,course_list';

//      $CFG->defaultblocks_topics = 'participants,activity_modules,search_forums,course_list:news_items,calendar_upcoming,recent_activity';

//      $CFG->defaultblocks_weeks = 'participants,activity_modules,search_forums,course_list:news_items,calendar_upcoming,recent_activity';

//

// These blocks are used when no other default setting is found.

//      $CFG->defaultblocks = 'participants,activity_modules,search_forums,course_list:news_items,calendar_upcoming,recent_activity';

Regards